Electropolishing is the electrolytic removal of metal in a highly ionic solution by means of a electric potential and current. In layman’s terms it is reverse electroplating. Electropolishing improves the surface finish of the metal by smoothing out (or removing) the high spots on the surface. Up to a 50% improvement in the average roughness height can be accomplished by electropolishing. Another advantage of electropolishing is the chemical interactions that occur on the surface of the metal. Electropolishing levels the grain boundaries of the metal, this removes sites for chemicals, dirt and microorganisms, another benefit is the reduction of surface area of the grain boundaries. Because electropolishing is performed in a chemically aggressive environment, any invisible defects in the material before electropolishing will appear after electropolishing. Furthermore, the metal removal is selective, free iron is readily removed from the surface whereas Chromium, Nickel and carbon are not. It is theorized that the Nickel, Chromium and Carbon actually form a Nichrome composition at the surface, Nichrome has excellent corrosion resistant properties. The free Chromium forms Chromium oxides that makes up the passive layer. The electropolishing process performs chemical passivation at least as good with other methods.